Unit 4 | Motor Flashcards
(163 cards)
1
Q
What are motor activities?
A
Motor activities are movements of the body that are produced by the muscles under the control of the nervous system.
2
Q
What are the two main types of motor activities?
A
Automatic movements
Purposeful movements
3
Q
What are automatic movements?
A
Automatic movements are performed without conscious thought, like walking, breathing, or blinking.
4
Q
What are purposeful movements?
A
Purposeful movements are planned, goal-directed actions that require thought, like writing, picking up a cup, or playing an instrument.
5
Q
: What is praxis?
A
Praxis is the ability to plan and perform purposeful movements. It involves thinking about what to do and how to do it.
6
Q
Why is praxis important?
A
Praxis allows us to interact effectively with our environment by enabling us to carry out complex motor tasks, such as dressing or using tools.
7
Q
What are the stages of praxis?
A
Ideation – Knowing what to do
Planning – Figuring out how to do it
Execution – Actually doing the movement
8
Q
What is an example of ideation in praxis?
A
Thinking, “I want to brush my teeth.”
9
Q
What is an example of planning in praxis?
A
Deciding how to hold the toothbrush and in what order to brush each part of the mouth.
10
Q
What is an example of execution in praxis?
A
Physically brushing your teeth with coordinated movements.
11
Q
What is the quote “Movement is an integral part of what it is to be alive” referring to?
A
It emphasizes that movement is essential to human functioning—emotionally, physically, and cognitively.
12
Q
What part of the brain is primarily involved in motor planning and execution?
A
The motor cortex, premotor cortex, cerebellum, and basal ganglia.
13
Q
What happens if there’s a problem with praxis?
A
A person may have dyspraxia, a condition where it’s difficult to plan or carry out motor tasks despite having the physical ability.
14
Q
How can you support someone with dyspraxia?
A
Use clear step-by-step instructions, allow extra time, and provide physical or visual modeling.
15
Q
What are somatic motor pathways?
A
Neural pathways that control voluntary and involuntary movements of the body’s skeletal muscles.
16
Q
What is an ascending pathway?
A
A pathway that carries sensory information from the body (periphery) up to the brain (cortex).
17
Q
What is a descending pathway?
A
A pathway that sends motor commands from the brain down to the muscles in the body.
18
Q
What does the pyramidal tract control?
A
Voluntary and conscious motor actions, like moving your arm to pick something up.
19
Q
What is the main function of the extrapyramidal tract?
A
It manages involuntary control, including the adjustment of automatic movements and reflexes.
20
Q
What are examples of actions controlled by the extrapyramidal tract?
A
Walking
Maintaining posture
Regulating muscle tone
Body alertness
Involuntary actions like urination and defecation
21
Q
What happens if the pyramidal tract is damaged?
A
There may be weakness or paralysis in voluntary movements, especially fine motor skills.
22
Q
What happens if the extrapyramidal tract is damaged?
A
Problems with muscle tone, reflexes, posture, and involuntary movements (e.g., tremors or rigidity).
23
Q
Which tract allows you to intentionally move your hand to write something?
A
The pyramidal tract.
24
Q
Which tract helps you keep your balance while standing still?
A
The extrapyramidal tract.
25
True or False: Both tracts work together to produce smooth, coordinated movement.
True. Voluntary movements (pyramidal) often need background control (extrapyramidal) to be effective.
26
What is the main function of the extrapyramidal tract?
It controls automatic, involuntary, and reflexive movements like posture, balance, and muscle tone.
27
Does the extrapyramidal system directly control muscles?
No — it modulates and regulates movement indirectly, not through direct innervation of muscles.
28
Where does the extrapyramidal tract originate?
From subcortical areas, including the midbrain, basal ganglia, and cerebellum.
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What is the destination of extrapyramidal pathways?
They end in the spinal cord, where they influence lower motor neurons that activate muscles.
30
What are the four main descending tracts of the extrapyramidal system?
Rubrospinal
Reticulospinal
Vestibulospinal
Tectospinal
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What does the rubrospinal tract control?
Fine motor control of distal limb muscles (especially upper limbs).
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What does the reticulospinal tract control?
Regulates flexion and extension of muscles in the limbs and influences muscle tone.
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What does the vestibulospinal tract control?
Maintains balance and posture, especially in response to head movements and changes in body position.
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What does the tectospinal tract control?
Coordinates eye, head, and torso movements, especially in response to visual and auditory stimuli.
35
How does the basal ganglia contribute to the extrapyramidal system?
It helps initiate, suppress, and fine-tune automatic movements.
36
What role does the cerebellum play in the extrapyramidal system?
It ensures smooth, coordinated, and precise movement through constant feedback.
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What is an example of an automatic movement controlled by the extrapyramidal system?
Adjusting your posture while walking without thinking about it.
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What is the main function of the extrapyramidal tract?
The extrapyramidal tract is responsible for involuntary, automatic movements such as posture, balance, reflexes, and muscle tone. Unlike voluntary movements (like picking up a pen), these actions happen without conscious effort.
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Does the extrapyramidal system send direct signals to muscles?
No. Unlike the pyramidal tract, which directly controls skeletal muscles, the extrapyramidal system works through modulation and regulation of movement. It adjusts and fine-tunes signals that go from the brain to the muscles via lower motor neurons.
40
Where does the extrapyramidal tract originate?
It starts in subcortical areas of the brain (below the cerebral cortex), including the midbrain, basal ganglia, and cerebellum, which are all involved in regulating movement patterns.
41
What is the pathway of extrapyramidal signals from the brain to the muscles?
From subcortical regions, signals travel through descending tracts in the spinal cord, eventually influencing inferior (lower) motor neurons that connect to the muscles.
42
What are the four major descending tracts in the extrapyramidal system?
Rubrospinal tract
Reticulospinal tract
Vestibulospinal tract
Tectospinal tract
Each tract has a specialized function related to movement control.
43
What is the role of the rubrospinal tract?
It originates in the red nucleus of the midbrain and helps control fine motor movements in the upper limbs, especially in tasks requiring precise coordination (e.g., adjusting your grip).
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What does the reticulospinal tract regulate?
Coming from the reticular formation in the brainstem, this tract helps coordinate flexion and extension of limb muscles and contributes to muscle tone—essential for basic movement readiness and posture.
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What is the function of the vestibulospinal tract?
t arises from the vestibular nuclei in the brainstem and plays a major role in maintaining balance and postural stability, especially during movement and when responding to changes in head position.
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What does the tectospinal tract coordinate?
Originating from the superior colliculus in the midbrain, it connects the eyes, head, and upper body. It controls reflexive orientation movements like turning your head toward a sound or visual stimulus.
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How does the basal ganglia contribute to movement control?
The basal ganglia are deeply embedded in the brain and help initiate and regulate automatic movement patterns, suppress unwanted movements, and adjust movement intensity—important for habits like walking.
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What is the role of the cerebellum in the extrapyramidal system?
The cerebellum refines movement by providing constant feedback on body position, speed, and coordination. It ensures fluidity, accuracy, and balance during automatic and learned motor tasks.
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What are examples of automatic movements controlled by the extrapyramidal system?
Walking steadily without thinking, adjusting posture while sitting, or shifting weight to maintain balance when someone bumps into you.
50
What is extrapyramidal impairment?
It’s a dysfunction in the extrapyramidal system, which leads to problems with involuntary movement control, such as posture, muscle tone, and coordination.
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What aspects of movement are most affected by extrapyramidal damage?
The execution of movements becomes impaired—movements may lose fluency (smoothness) and efficiency (speed and coordination).
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Which brain structures are commonly involved in extrapyramidal impairments?
Mainly subcortical regions, especially the basal ganglia and the thalamus, which are essential for regulating automatic and habitual movements.
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What are some common causes of extrapyramidal disorders?
Neurodegenerative diseases (e.g., Parkinson’s disease)
Brain tumors
Lesions, especially in the basal ganglia
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Why are basal ganglia lesions particularly important in extrapyramidal disorders?
The basal ganglia are central to regulating movement; damage here disrupts the fine-tuning of motor output, often leading to rigidity, tremors, slowness, or involuntary movements.
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What are some signs of extrapyramidal symptoms (EPS)?
Tremors
Muscle rigidity
Bradykinesia (slowness of movement)
Postural instability
Involuntary movements (like chorea or dystonia)
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What is a common disease involving extrapyramidal system damage?
Parkinson’s disease, which is caused by the degeneration of dopamine-producing neurons in the substantia nigra, a part of the basal ganglia.
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How do extrapyramidal impairments differ from pyramidal impairments?
Pyramidal impairments affect voluntary movements (e.g., weakness, spasticity).
Extrapyramidal impairments affect automatic and regulatory aspects of movement (e.g., tremors, rigidity, poor posture).
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What type of motor disorder is typically caused by basal ganglia lesions?
Hyperkinetic disorders, which involve excessive or involuntary movements, such as tremors, chorea, or dystonia.
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What are tremors?
Tremors are rhythmic, involuntary motor discharges that result in shaking or oscillating movements, usually of the limbs or head.
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What causes tremors neurologically?
They often result from lesions in either the cerebellum or the basal ganglia, both of which are involved in fine-tuning and regulating movement.
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What are the three main types of tremors?
Resting (Parkinsonian) tremors
Essential tremors
Intentional tremors
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What are resting tremors (also called static or Parkinsonian tremors)?
These occur when the body is at rest, especially in the distal muscles (like hands or fingers). They are commonly associated with Parkinson’s disease and often disappear during voluntary movement.
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What are essential tremors?
These happen when a person starts a voluntary movement, such as reaching for a cup. They affect distal muscles and are often familial (genetic) and non-progressive.
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What are intentional tremors (also called action tremors)?
These occur at the end of an intentional movement, like touching your finger to your nose. They involve 4–10 discharges per second and are typically due to cerebellar lesions.
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Which type of tremor is commonly linked to cerebellar damage?
Intentional tremors—they appear during the execution of a goal-directed action, especially as the movement concludes.
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Which structure is most involved in resting tremors?
The basal ganglia, particularly when affected by Parkinson’s disease.
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Which structure is most involved in intentional tremors?
The cerebellum, due to its role in coordinating fine motor movements.
68
What is chorea?
Chorea is a movement disorder characterized by brief, rapid, and non-repetitive involuntary movements that often look like fidgeting or dancing and primarily affect the limbs.
69
Can choreic movements occur during sleep?
Yes, choreic movements can persist even during sleep, although they often decrease in frequency.
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Are choreic movements focal or generalized?
They can be focal (affecting one area of the body) or generalized (affecting multiple areas).
71
What causes Huntington’s disease at the genetic level?
It is a hereditary condition caused by a mutation on Chromosome 4, involving excessive repeats of the CAG triplet in the HTT gene.
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What are common symptoms of Huntington’s disease beyond movement disorders?
Muscle spasms
Personality changes
Progressive memory loss (cognitive decline)
Language disorders
Gait and walking instability
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What brain structures are most affected in Huntington’s disease?
Primarily the basal ganglia, especially the caudate nucleus and putamen, which degenerate over time.
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s Huntington’s disease curable?
No, it is progressive and incurable, though symptoms can be managed with medications and therapy.
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What is the inheritance pattern of Huntington’s disease?
Autosomal dominant, meaning a child has a 50% chance of inheriting it if one parent carries the gene.
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What is athetosis?
Athetosis is a movement disorder characterized by slow, irregular, and writhing involuntary movements, often appearing twisting or contorted.
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What does it mean that athetosis has no fixed position?
The limbs or body parts are constantly shifting, never holding a single position, making it difficult to maintain posture or execute precise movements.
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Where are athetotic movements usually seen?
They are most frequent in distal areas (e.g., fingers, hands, feet), but can occur anywhere in the body.
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How does athetosis affect movement control?
It causes poor coordination and loss of movement accuracy, making tasks like writing, grasping, or buttoning clothes difficult.
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What brain regions are involved in athetosis?
Most often due to damage in the basal ganglia and thalamus, which are crucial for regulating automatic and fine motor activity.
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Is athetosis congenital or acquired?
It can be either:
Congenital (e.g., due to cerebral palsy)
Acquired (e.g., due to brain injury, stroke, or infection affecting deep brain structures)
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How is athetosis different from chorea?
Chorea = rapid, jerky, unpredictable movements.
Athetosis = slow, writhing, and flowing movements.
Sometimes they appear together (called choreoathetosis).
83
What are tics?
Tics are sudden, brief, stereotyped, and involuntary muscle movements or vocalizations that often appear intentional but are not under conscious control.
84
Do tics change with emotional state or sleep?
Yes. Tics often increase with emotional stress (like anxiety or excitement) and may persist during sleep, though they are usually less intense.
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What body areas can be affected by tics?
They can involve the face, neck, trunk, joints, and even functions like respiration, speech (linguistic tics), and swallowing (deglutition tics).
86
What is Gilles de la Tourette Syndrome?
A neurological disorder involving both motor tics (like blinking, shoulder shrugging) and vocal tics (like throat clearing, words). Tics may be simple or complex.
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What is coprolalia?
A rare symptom of Tourette Syndrome, found in about 20% of cases, where the person involuntarily utters obscene or socially inappropriate words.
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What causes Tourette Syndrome?
The exact cause is unknown, but it is believed to involve both genetic and environmental factors, and a failure of inhibition within the basal ganglia circuitry.
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What is the difference between Tourette Syndrome (TS) and tics?
Tics may be isolated and mild.
Tourette Syndrome is a chronic disorder involving both motor and vocal tics, usually starting in childhood, and is more functionally impairing (social, emotional, behavioral).
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What is the neurological basis of tics and TS?
Likely due to disinhibition in the basal ganglia, which causes excessive, uncontrolled activation of motor circuits.
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What is dystonia?
A movement disorder involving slow, involuntary, and sustained muscle contractions that lead to abnormal, twisted postures or repetitive movements.
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What causes the abnormal postures in dystonia?
They result from prolonged muscle contractions, which can involve one muscle group or multiple, leading to torsion, twisting, or fixed postures.
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Which neurotransmitter imbalances are linked to dystonia?
Deficits in dopamine or GABA (gamma-aminobutyric acid) in the basal ganglia, which disrupt normal movement inhibition and coordination.
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What brain region is commonly involved in dystonia?
The basal ganglia, which help control muscle tone and movement regulation.
95
What is myoclonus?
Myoclonus consists of brief, shock-like muscle jerks that result from sudden contraction or relaxation of one or more muscles.
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How is myoclonus different from dystonia or tremors?
Myoclonus is very fast and resembles a jerk or twitch.
Dystonia is sustained and slower.
Tremors are rhythmic and repetitive.
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What can trigger myoclonus?
It can be caused by epilepsy, metabolic disturbances, neurodegenerative diseases, or be benign (e.g., hiccups or sleep starts).
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Is myoclonus always pathological?
No. While it can be part of serious neurological conditions, benign forms (like hypnic jerks during sleep) are normal and not a sign of disease.
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What are mannerisms?
Mannerisms are peculiar, purposeful-looking gestures or movements that are non-disruptive and often more complex and prolonged than typical involuntary movements.
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Are mannerisms involuntary?
They are semi-voluntary or automatic, meaning the person may not fully control them but can sometimes suppress or modify them.
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What makes mannerisms distinct from tics or stereotypies?
Mannerisms are usually longer, more elaborate, and may resemble normal behavior exaggerated in an odd or excessive way. Unlike tics, they are less abrupt and often socially tolerated.
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What are stereotypies?
Stereotypies are repetitive, rhythmic, fixed movements or vocalizations, which may be simple (like body-rocking, head-nodding, finger-tapping) or complex (like hand-flapping, waving, or pacing).
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Are stereotypies always pathological?
No. While they are common in neurodevelopmental conditions (e.g., autism), they also occur in typically developing children, especially when excited or focused.
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How are stereotypies different from tics?
Stereotypies are rhythmic, predictable, and often soothing.
Tics are sudden, unpredictable, and urge-driven.
Stereotypies typically start earlier in life and are more regular.
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What disorders commonly include stereotypies?
Autism spectrum disorder (ASD)
Intellectual disabilities
Sensory processing disorders
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What is ballism?
Ballism is a movement disorder characterized by sudden, violent, flinging movements of the limbs, especially involving proximal joints (like shoulders and hips).
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What is the difference between ballism and hemiballism?
Ballism affects both sides of the body (bilateral).
Hemiballism affects only one side (contralateral) to a brain lesion.
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Which joints are mainly affected by ballism?
The large proximal joints, such as the shoulder, hip, and elbow.
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What brain structure is primarily affected in hemiballism?
The subthalamic nucleus, part of the basal ganglia circuitry, typically due to lesions such as stroke, trauma, tumor, or vascular malformation.
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Why does damage to the subthalamic nucleus cause hemiballism?
It disrupts excitatory signals to the globus pallidus, which reduces inhibition of movement, leading to excessive motor activity.
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Can other brain structures be involved in ballism?
Yes, although rarely, lesions in the putamen may also cause ballism-like symptoms
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Is ballism permanent?
Not usually. It often resolves over time, either spontaneously or with treatment.
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How common is ballism?
It is very rare, especially in its pure form.
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What is ataxia?
Ataxia is a movement disorder characterized by abnormal, uncoordinated, and often trembling movements, especially when trying to perform voluntary actions.
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What is typically impaired in ataxia?
Fluency of movement
Direction and grading (adjusting force/speed)
Sequencing of actions
Coordination and timing
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What causes the uncoordinated movements in ataxia?
An inability to accurately measure distance, force, and timing of muscle activity—like missing when trying to touch your nose (dysmetria).
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What part of the brain is responsible for ataxia?
The cerebellum, which is essential for motor coordination, balance, and error correction during movement.
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How is ataxia different from extrapyramidal symptoms like tremor or chorea?
Ataxia = loss of coordination and control
Extrapyramidal symptoms = involuntary movements (e.g., tremor, chorea)
Ataxia is more about precision, not excess movement.
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What types of tasks are most difficult for someone with ataxia?
Walking straight
Reaching accurately
Rapid alternating movements
Maintaining balance
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What are common signs of cerebellar ataxia?
Wide-based gait
Dysmetria (overshooting/undershooting)
Intention tremor
Speech problems (scanning speech)
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What is praxis?
Praxis refers to voluntary, coordinated motor actions performed with the purpose of achieving a specific goal. It involves more than just reflexes—it's about planning and executing intentional movements.
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What are the 3 main steps in the process of praxis?
Reception of sensory information – The brain receives and processes input from the environment (e.g., visual, tactile, auditory).
Establishment of a general plan – This involves forming a strategy, including considerations for timing, flow, rhythm, sequencing, and transfer of weight.
Motor execution – The plan is carried out with precise movements to complete the action.
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What is involved in the establishment of a general plan in praxis?
It includes deciding on the timing, flow, rhythm, sequencing of the movement, and the transfer of weight to ensure smooth and coordinated action.
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What role does sensory information play in praxis?
Sensory information is crucial because it helps the brain understand the environment, adjust the motor plan, and ensure the actions are appropriate to the goal (e.g., how to grasp a cup based on its shape and position).
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What happens in the motor execution phase of praxis?
The brain translates the plan into physical movements, adjusting in real-time if necessary, to complete the intended goal (e.g., picking up a cup and drinking from it).
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Why is praxis important for daily activities?
Praxis is essential for performing volitional movements that involve planning and coordination, such as writing, driving, or dressing, where the body needs to adapt and respond to the environment purposefully.
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How is praxis related to motor learning?
Praxis is a fundamental part of motor learning, as it involves the brain’s ability to plan, coordinate, and execute movements that are necessary for new and familiar tasks. Without proper praxis, motor actions would be inefficient or impossible.
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: What is the role of the prefrontal cortex in motor activities?
The prefrontal cortex is involved in planning and making the decision to initiate movement. It helps with higher-level thinking about what needs to be done before any action begins.
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What does the premotor cortex do?
The premotor cortex programs the sequence or pattern of the movement, translating the plan into a specific motor strategy for execution.
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What is the function of the posterior parietal cortex?
The posterior parietal cortex integrates sensory information to provide a spatial representation of movements, allowing for coordination between the body and its surroundings. This is often called the praxis or praxicon (the motor map).
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What is the role of the primary motor cortex in motor control?
The primary motor cortex initiates voluntary movements and is responsible for accuracy, coordination, and strength of those movements. It controls fine motor control of specific body parts.
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How does the primary somatosensory cortex contribute to motor function?
The primary somatosensory cortex receives sensory information and provides feedback during and after movement. It is critical for assessing sensory inputs to ensure the movement is on track and adjusts actions accordingly.
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How do the prefrontal cortex and premotor cortex work together in motor control?
The prefrontal cortex creates a plan to start a movement, while the premotor cortex takes that plan and organizes the sequence or pattern of the movement, ensuring it happens in the correct order and with the right timing.
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What happens if there’s damage to the posterior parietal cortex?
Damage to the posterior parietal cortex can lead to spatial coordination problems, where an individual might struggle with understanding their body’s position in space, leading to difficulties in performing accurate motor actions (e.g., reaching for objects).
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How do the primary motor cortex and somatosensory cortex collaborate in movement?
The primary motor cortex initiates movement, while the somatosensory cortex provides real-time sensory feedback, allowing adjustments in motor execution for better accuracy and coordination.
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How does the primary motor cortex contribute to movement strength?
The primary motor cortex is responsible for controlling the force of muscle contractions. It adjusts the strength of movements by activating specific motor neurons based on the task at hand.
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What is the pyramidal tract?
The pyramidal tract is a direct motor pathway that carries voluntary motor signals from the associative brain areas (like the cortex) to the motor neurons, allowing for precise and controlled movements.
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Where does the pyramidal tract originate?
It originates in the associative areas of the brain, including the premotor, supplementary motor, and motor areas of the cortex, as well as subcortical regions.
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What is the main function of the pyramidal tract?
The main function is direct innervation of motoneurons, meaning it sends motor commands from the brain directly to the muscles for voluntary movement.
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What are the two descending tracts of the pyramidal system?
Corticospinal tract: From the cortex to the spinal cord, controlling movements of the body.
Corticobulbar tract: From the cortex to the brainstem, controlling movements of the head and neck.
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What is the function of the corticospinal tract?
The corticospinal tract is responsible for controlling body movements, including fine motor control, by transmitting signals from the motor cortex to the spinal cord.
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What does the corticobulbar tract control?
The corticobulbar tract controls voluntary movements of the head and neck, transmitting signals from the motor cortex to the brainstem, which in turn affects cranial nerves involved in facial and speech movements.
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How is the pyramidal tract different from the extrapyramidal tract?
The pyramidal tract involves direct voluntary control over motor activity (like fine motor skills), while the extrapyramidal tract influences involuntary movements, posture, and coordination, often involving more complex subcortical areas.
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What is the pathway of the corticospinal tract from the brain to the muscles?
A:
Starts in the motor cortex (primary motor and premotor areas).
Passes through the internal capsule and the medullary pyramids.
Decussates (crosses over) at the medulla and descends to the spinal cord, where it synapses with motoneurons that control the body muscles.
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What is the pathway of the corticobulbar tract?
Starts in the motor cortex (primary motor area).
Descends to the brainstem, where it synapses with cranial motor nuclei (responsible for facial muscles, swallowing, and speaking).
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What are the 3 main stages of motor activity?
The 3 main stages of motor activity are:
Planification (planning)
Movement (execution of the plan)
Execution (completion of the motor action).
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What are tertiary areas in the context of motor activity?
Tertiary areas involve higher-level association cortices responsible for integrating complex sensory and motor information, forming motor plans, and coordinating abstract decision-making (e.g., prefrontal cortex).
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What are secondary areas in motor activity?
Secondary areas include regions like the premotor cortex and supplementary motor area, which contribute to the organization and coordination of motor actions based on plans created by the tertiary areas.
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What are primary areas in motor activity?
Primary areas are the primary motor cortex (for initiating movement) and the primary somatosensory cortex (for processing sensory feedback). They are involved in direct execution and fine-tuning of motor actions.
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What role do subcortical areas play in motor activity?
Subcortical areas, like the basal ganglia and cerebellum, provide crucial coordination, modulation, and fine-tuning of movements. They assist in adjusting motor activity for smooth and controlled movements.
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What is the role of associative areas in motor planning?
Associative areas (such as the prefrontal cortex) are responsible for complex planning, integrating sensory inputs, and making decisions about the purpose and goal of a movement before it is executed.
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How do the basal ganglia contribute to motor activities?
The basal ganglia are involved in modulating and refining motor movements, particularly in controlling smoothness, coordination, and preventing involuntary movements (like tremors or tics).
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What role does the cerebellum play in motor execution?
The cerebellum is essential for balance, coordination, and fine-tuning motor movements. It provides real-time feedback for adjustments during motor tasks to ensure precision and smoothness.
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What does the premotor cortex do in motor planning?
The premotor cortex organizes the sequence of movements needed to accomplish a task and coordinates muscle groups for execution. It helps prepare and refine movements before the primary motor cortex takes over.
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What is the role of the supplementary motor area (SMA) in motor planning?
The supplementary motor area (SMA) is involved in sequencing complex movements, particularly those that require bilateral coordination (e.g., both hands or both sides of the body).
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What are the motor areas and spinal tracts?
The motor areas (like the primary motor cortex) initiate voluntary movements. The spinal tracts (like the pyramidal tract and extrapyramidal tracts) carry these motor commands from the brain to the spinal cord and then to the muscles.
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What happens when the extrapyramidal tract is impaired?
Impairment of the extrapyramidal tract results in loss of fluency and efficiency of movements. This leads to difficulty in coordinating smooth, voluntary movements and affects posture, balance, and involuntary action
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What are common symptoms of extrapyramidal impairment?
Common symptoms include tremors, rigidity, bradykinesia (slowness of movement), and loss of fluidity in movement, often seen in conditions like Parkinson’s disease or other neurodegenerative disorders.
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What are apraxias and which tract is associated with them?
Apraxias are motor disorders resulting from damage to the pyramidal tract, causing difficulty in planning and executing purposeful movements, even though the individual has no physical weakness. This leads to problems with tasks such as buttoning a shirt or writing.
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What happens when the pyramidal tract is impaired?
Pyramidal tract impairment typically results in paralysis and weakness of specific body parts. This often includes spasticity or loss of voluntary control over muscles, particularly those involved in fine motor movements.
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What are the key differences between extrapyramidal and pyramidal tract impairments?
Extrapyramidal impairments mainly affect the smoothness and coordination of movements (e.g., tremors, rigidity).
Pyramidal impairments result in loss of voluntary motor control, including paralysis and apraxias (difficulty planning purposeful actions).
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What does paralysis indicate in the context of pyramidal tract impairment?
Paralysis due to pyramidal tract impairment occurs when there is damage to the motor pathways from the brain to the muscles, leading to inability to move specific muscle groups or complete loss of function in certain body parts.
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